[PATCH 6.4 556/800] usb: dwc2: Fix some error handling paths

Greg Kroah-Hartman
2023-07-16T20:18:53Z

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

[ Upstream commit ada050c69108bc34be13ecc11f7fad0f20ebadc4 ]

dwc2_driver_probe() calls dwc2_lowlevel_hw_init() which deassert some reset
lines.
Should an error happen in dwc2_lowlevel_hw_init() after calling
reset_control_deassert() or in the probe after calling
dwc2_lowlevel_hw_init(), the reset lines remain deasserted.

Add some devm_add_action_or_reset() calls to re-assert the lines if needed.

Update the remove function accordingly.

This change is compile-tested only.

Fixes: 83f8da562f8b ("usb: dwc2: Add reset control to dwc2")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/c64537b5339342bd00f7c2152b8fc23792b9f95a.1683306479.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/dwc2/platform.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 5aee284018c00..5cf025511cce6 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -203,6 +203,11 @@ int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
return ret;
}

+static void dwc2_reset_control_assert(void *data)
+{
+ reset_control_assert(data);
+}
+
static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
{
int i, ret;
@@ -213,6 +218,10 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
"error getting reset control\n");

reset_control_deassert(hsotg->reset);
+ ret = devm_add_action_or_reset(hsotg->dev, dwc2_reset_control_assert,
+ hsotg->reset);
+ if (ret)
+ return ret;

hsotg->reset_ecc = devm_reset_control_get_optional(hsotg->dev, "dwc2-ecc");
if (IS_ERR(hsotg->reset_ecc))
@@ -220,6 +229,10 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
"error getting reset control for ecc\n");

reset_control_deassert(hsotg->reset_ecc);
+ ret = devm_add_action_or_reset(hsotg->dev, dwc2_reset_control_assert,
+ hsotg->reset_ecc);
+ if (ret)
+ return ret;

/*
* Attempt to find a generic PHY, then look for an old style
@@ -339,9 +352,6 @@ static int dwc2_driver_remove(struct platform_device *dev)
if (hsotg->ll_hw_enabled)
dwc2_lowlevel_hw_disable(hsotg);

- reset_control_assert(hsotg->reset);
- reset_control_assert(hsotg->reset_ecc);
-
return 0;
}

--
2.39.2